Machine for cutting or shredding plant leaves, paper, and the like



pril 21, 1936.

A. PODMORE MACHINE FOR CUTTING OR SHREDDING PLANT LEAVES, PAPER AND THE LIKE Filed [May 10, 1935 3 Sheets-Sheet l A. PODMORE April 21, 1936.

MACHINE FOR CUTTING OR SHREDDING PLANT LEAVES, PAPER AND THE LIKE 5 Sheets-Sheet 2 Filed May 10, 1935 April 21, 1936.. PQDMORE 2,@38,5@2

MACHINE FOR CUTTING OR SHREDDING PLANT LEAVES, PAPER AND THE LIKE Filed May 10, 1935 a Sheets-Sheet 5 Patented Apr. 21, 1936 PATENT OFFICE MACHINE FOR CUTTING OR SHREDDING PLANT LEAVES, PAPER, AND THE LIKE Arthur Podmore, London, England, assignor to American Machine & Foundry Company, New York, N. Y., a corporation of New Jersey Application May 10, 1935, Serial No. 20,710 In Great Britain March 27, 1934 8 Claims. (01. 146-122) v This invention relates to machines for cutting or shredding plant leaves, paper and like materials, of the type comprising intermeshing rotary disc knives.

In such cutting machines when used, for example, for cutting tobacco leaves into shreds of a width of about millimetre, a considerable number of discs'is employed, and it is found that owing to the rubbing contact of the discs at the cutting zone, heat is generated which may have a detrimental effect.

It is an object of the present invention to provide improvements in cutting machines of the type in question whereby the generated heat is readily dissipated.

According to the invention, in cutting machine comprising sets of intermeshing rotary disc knives, means are provided. whereby cooling fluid such as air or water may be directed upon the cutting discs or caused to percolate between such discs in order to keep them at the desired temperature or prevent too great a temperature rise.

The invention also consists in a cutting machine comprising sets of intermeshing rotary disc knives, wherein the disc knives are mounted upon a chambered support having perforations whereby cooling fluid may pass from the chamber and between the disc knives or vice versa.

A valve element may be provided within the chambered support to close the perforations to the passage of the cooling gases or the like while such perforations are adjacent the cutting zone.

Further features of the invention will be hereinafter described and defined in the claims.

In the accompanying drawings:

Figure 1 is a longitudinal section through the axis of a cutter.

Figure 2 is a cross section at right angles to the axis.

v Figure 3 is a detail on an enlarged scale indicating the fiow of the cooling gases between the disc knives.

In carrying the invention into effect according to one convenient mode, the supporting and driving shaft for each set of disc knives is formed with an axial chamber ill to which air under pressure is supplied. This chamber may be formed by the provision of a pair of spaced shafts H and I2 having flanges l3 and I l upon which a sleeve I5 is mounted.- I'he sleeve is provided with a number of keyways [6 extending parallel with the axis and in which projections I! on the knife discs l8 fit, whereby a driving connection is formed between the knives and the sleeve. The shaft I4 is formed hollow to accommodate a tube l9 by which the chamber is coupled up to a suitable source of air under pressure.

In addition to the knife discs (8, the sleeve supports spacing elements 20 which are similarly keyed upon the sleeve l5. At one end of the as- 5 sembly a spring-pressed disc element 21 is provided adapted to engage the end knife disc [8 and exert a longitudinal pressure parallel to the axis so as to force the discs together against anabutment disc 22 which is provided at the other end of the assembly.

Mounted within the shaft chamber [0 is a valve control 23 for the'air which is adapted to be stationary and for this purpose is provided with a boss 24 fixed to thetube l9 passing through the hollow shaft [4 aforesaid. The valve control comprises an arcuate plate or member 24 which extends the whole length of the chamber and which may extend circumferentially for about 90. The plate 24 is located in a position adjacent the 0 interengaging zone of the disc cutters as will be seen in Figure 2 whereby the cooling air will not impinge upon the portion of the discs in said zone.

The supporting sleeve I5 is provided with a se- 25 ries of apertures 25 through which the air from the chamber l 0 may pass into the spaces between the disc knives. As the sleeve shaft rotates, the apertures 25 remain open until they pass into or adjacent the cutting zone, when they will be closed by the valve plate 24 so that there will be no currents of air passing outwardly adjacent the cutting zone.

In order to permit a free passage of the air, the cutter discs l8 and the spacing elements 20 are cut away or slotted in the portions extending between the keys or projections ll. Thus each spacer element 20 may have curved recesses 26 in its inner periphery adjacent the surface of the supporting sleeve, the full width of the elements only remaining adjacent each key. Similarly the cutter discs l8 may have arcuate slots 21 near their inner peripheries so that they coincide with the narrowed parts of the spacer elements, the slots 21, however, being about twice the width of such narrowed part. The supporting sleeve l5 adjacent these cut away portions may also be provided with a recessed surface or grooving 28 into which the perforations 25 in the sleeve open. By this arrangement the air passing from the interior of the chamber ID will find its way along the grooving 28 in the supporting sleeve and radially between the discknives l8, thence into the hollow spaces formed'by the curved slots 2'! in the disc knives and finally outwardly between the main portion of the discs (as indicated by the arrows in Figure 3) whereby the latter are cooled.

Arcuate or other suitably shaped clearing devices 29 mounted upon bars 30 may be provided extending upwardly between the discs adjacent the cutting zone.

The speed with which the air passes between the knives may be varied as desired, dependent upon the pressure of the air supply and the degree of cooling necessary.

It will be appreciated that by the use of a valve device the filtering or passage of the air between the disc knives will only take place at the parts of the latter away from the cutting zone. If desired, a hood device may be provided which may be under suitable suction in order to localize the cooling air and avoid its free dissipation into the atmosphere.

According to an alternative arrangement, cooling may be effected by drawing air inwardly between the knives.

This may be effected by applying suction to the tube l9.

Instead of using air or gas a liquid such as water or water vapour may be delivered to the chamber Ill and forced through the openings 25 and between the knives to cool them. With such an arrangement a cleansing action may also take place whereby the accumulated juices and gums from the tobacco may be removed from the knives.

According to a further form in which air is used for cooling, the neutral zone formed by the valve device 24 may extend only from the horizontal plane containing the axes of the cutters upwardly for about 30 to 45 the part of the disc cutters below such horizontal adjacent the cutting zone being subject to the air blast. With such an arrangement the clearing devices 28 may be dispensed with, the air current being utilized also for clearing the tobacco from the spaces between the discs.

I claim:-

' 1. A cutting machine comprising sets of intermeshing disc knives mounted to rotate upon parallel axes, rotary hollow shafts supporting the disc knives, said shafts having perforations in communication with the spaces between the discs, means for supplying compressed air to the hollow shafts, valve means located within the hollow shafts for controlling the flow of air through said perforations, said valve means comprising a curved wall in the intermeshing zone and extending upwardly from the horizontal plane of the axes of the cutter shafts, whereby air currents flowing outwardly from the disc knives, below such plane, operate to clear the cut material from the cutters.

2. The combination with sets of disc knives intermeshed to form a cutting zone, of chambered mounts supporting and rotating said knives, and means directing currents of cooling fluid through the chambers of said mounts over the surfaces of said knives, said mounts including axially aligned and flanged shafts spaced apart, and a sleeve supported and rotated by the flanges of said shafts and keyed to said knives.

3. The combination with sets of disc knives intermeshed to form a cutting zone, of chambered mounts supporting and rotating said knives, and means directing currents of cooling fluid through the chambers of said mounts over the surfaces of said knives, said mounts including axially aligned and flanged shafts spaced apart, sleeves supported and rotated by the flanges of said shafts and keyed to said knives, and annular spacers between said knives and keyed to said sleeves.

4. The combination with sets of disc knives intermeshed to form a cutting zone, of chambered mounts supporting and rotating said knives, and means directing currents of cooling fluid through the chambers of said mounts over the surfaces of said knives, said mounts including axially aligned and flanged shafts spaced apart, sleeves supported and rotate-d by the flanges of said shafts and keyed to said knives, annular spacers between said knives and keyed to said sleeves, and spring pressed devices holding said knives and said spacers together.

5. The combination with sets of disc knives intermeshed to form a cutting zone, of chambered mounts supporting and rotating said knives, and means directing currents of cooling fluid through the chambers of said mounts over the surfaces of said knives, said mounts including axially aligned and flanged shafts spaced apart, and sleeves supported and rotated by the flanges of said shafts and keyed to said knives and having perforations providing passages therethrough for the cooling fluid.

6. The combination with sets of disc knives intermeshed to form a cutting zone, of chambered mounts supporting and rotating'said knives, and means directing currents of cooling fluid through the chambers of said mounts over the surfaces of said knives, said means including perforations in the walls of said mounts and stationary valves within said mounts coacting with said perforations to bar currents of cooling fluid from said '7. The combination with sets of disc knives intermeshed to form a cutting zone, of chambered mounts supporting and rotating said knives, and means directing currents of cooling fluid through the chambers of said mounts over the surfaces of said knives, said means including perforations in the walls of said mounts, stationary valves within said mounts coacting with said perforations to bar currents of cooling fluid from said zone, and tubes in open communication with the chambers of said mounts to provide for passage of currents of cooling fluid therethrough.

8. A cigarette tobacco shredder comprising in combination, two gangs made up of sets of circular cutting disks, means mounting said gangs for rotation on parallel axes with the peripheral portion of the disks of one gang intermeshing between the peripheral portions of the disks of the other gang, said means including hollow rotors extending transversely through said disks, sets of spacer disks arranged alternately between adjacent cutting disks to space the peripheral portions of said disks, ports through said rotors, said disks being provided with transverse openingsadjacent their inner periphery with the openings in one set of disks opening on the inner periphery thereof, providing passages from said ports to the spaces between the peripheries of the cutting disks to permit passage of fluid from the interior of said rotors to said spaces.

ARTHUR PODMORE. 

